Hello all I am new here and I have a transmission issue.
I have a 1994 Bonn. in which I have transplanted the drive train of 1994 Buick Lasaber.
The new drive train has 47000 miles on it. The engine runs fine but the transmission has to be cold to shift into overdrive after 7-10 miles it will no longer shift into overdrive or lock up the torque converter. At 60 mph the rpmí* when in OD and TC locked are about 1500-1600. When not in OD it is 2500-2600. I have replaced the vacuum modulator and changed the tranny fluid. I donít know of any differences between the Buick and the Pontiac to cause this. I have read on this web sight about wiring troubles and shift solenoids. How do you test for a wiring problem or a solenoid problem? I really need to fix this soon so any help is greatly appreciated.